How many types of event of event we have ?Best event is GM events and that is base on the GM is skill Second is player events that player create by meet with other players , can be good can be bad. This is the main contents of MMORPG .

The player events is complex , sometime just say "hello" to other also a type of events , the more tool you give for player to interface with other , more complex events it create .

Last is game events that auto start when condition meet

Monster spawn , special quest spawn , boss spawn ect

For example if you over hunt the mobs in a map , boss will come out and no more mob spawn until you take down the boss , everyone who in the map get a quest that reward when you hunt down that boss.

When you make an MMORPG events , quests , you need to understand that player will not play quests alone and want the quest to be repeatable . Nearly all MMORPG developer failed to understand this .

If you are parks maker , you will understand this . Who the **** that going to play again a park that you only have 1 run over the start to the end and say : "sorry we out of contents so you have to get out or walk around and watch other play"